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I use partimage, a Linux-based solution that takes full-partition or full-disk images and saves them as files. It can run across the network (by using partimaged on the server being used as storage) or by simply mounting a network share at some local folder, then saving at that folder.

If you use Drive Snapshot it can write images to the network while the computer is running. Obviously you can't restore an image while the OS is running. For that I use a WinPE or BartPE boot CD or USB key.

WinPE is based on Vista while the last BartPE I saw was based on 2003/XP and needs some messing around to add drivers for the latest hardware. You can get a copy of the Windows Automated Installation Kit (Windows AIK) from www.microsoft.com/downloads while BartPE is available from www.nu2.nu/pebuilder.